Octree

Class representing a hierarchical tree data structure used to partition 3D space. An octree is a hierarchical tree data structure used to partition a three-dimensional space by recursively subdividing it into eight octants. Be careful when using the octree cause building it will use recursion which can fill up the memory. Make sure to use good balanced values for trianglesPerLeaf and maxLevel! Octree can be used in games to compute collision between the game world and colliders from the player or other dynamic 3D objects.

Methods

Octree(u32 trianglesPerLeaf, u32 maxLevel)

Constructor to create new octree

trianglesPerLeaf	tris per subTree before split	8
maxLevel	maximum depth of Octree	16

Octree& addTriangle(const Triangle& triangle)

Adds the given triangle to the Octree

triangle

triangle to add

Octree& calcBox()

Prepares box for the build

Octree& split(u32 level)

Splits the Octree recursively when building

level

current level

Octree& build()

Builds the Octree

Octree& clear()

Clears the Octree by making it empty

void getRayTriangles(const Ray& ray, vector<Triangle*>& triangles)

Computes the triangles that potentially intersect with the given ray

ray	ray to test
triangles	target array that holds the triangles

void getSphereTriangles(const Sphere& sphere, vector<Triangle*>& triangles)

Computes the triangles that potentially intersect with the given bounding sphere

sphere	sphere to test
triangles	target array that holds the triangles

void getBoxTriangles(const Box3& box, vector<Triangle*>& triangles)

Computes the triangles that potentially intersect with the given bounding box

box	bounding box
triangles	target array that holds the triangles

void getCapsuleTriangles(const Capsule& capsule, vector<Triangle*>& triangles)

Computes the triangles that potentially intersect with the given capsule

capsule	capsule to test
triangles	target array that holds the triangles

void* boxIntersect(const Box3& box)

Performs a bounding box intersection test with this Octree

box

bounding box to test

void* sphereIntersect(const Sphere& sphere)

Performs a bounding sphere intersection test with this Octree

sphere

bounding sphere to test

void* capsuleIntersect(const Capsule& capsule)

Performs a capsule intersection test with this Octree

capsule

capsule to test

void* rayIntersect(const Ray& ray)

Performs a ray intersection test with this Octree

ray

ray to test

void* triangleBoxIntersect(const Box3& box, const Triangle& triangle)

Computes the intersection between the given bounding box and triangle

box	bounding box to test
triangle	triangle to test

void* triangleCapsuleIntersect(const Capsule& capsule, const Triangle& triangle)

Computes the intersection between the given capsule and triangle

capsule	capsule to test
triangle	triangle to test

void* triangleSphereIntersect(const Sphere& sphere, const Triangle& triangle)

Computes the intersection between the given sphere and triangle

sphere	sphere to test
triangle	triangle to test

Octree& fromGraphNode(Object3D& group)

Constructs the Octree from the given 3D object

group

scene graph node

const vector<Octree*>& getSubTrees() const

Gets the child octree nodes

Properties

bounds	Box3	bounds of the Octree (no margin applied)
box	Box3*	base box that encloses the entire Octree
enabled	bool	Active/inactive
id	u32	Unique identifier
isOctree	bool	Read-only tag
layers	Layers*	layers configuration for refine testing
maxLevel	u32	maximum level of the Octree (16)
name	string	Optional display name
trianglesPerLeaf	u32	number of triangles a leaf can store before split (8)
uuid	string	UUID string
version	u32	Bumps on change